With the increasingly high demand by people for better life, digital HD technologies have been experiencing a rapid development, and a variety of ultra HD audio/video devices have been continuously developed. Meanwhile, a variety of multimedia interfaces applicable for HD audio/video transmission, such as HDMI, DP, and the like, have been developed accordingly. There is an increasingly great information data amount for control signals transmitted by various multimedia interfaces. On the other hand, the conventional manner of copper wire transmission can achieve only a short distance transmission due to relatively high losses. At the same time, the manufacturing cost of high-grade cables increases sharply along with the increase of the cable length. Optical fiber transmission would be an excellent alternative.
A multimedia interface may simultaneously transmit a plurality of control signals, or at the same moment, a plurality of multimedia interfaces may simultaneously transmit their respective control signals. In optical fiber transmission lines, each transmission line requires its own laser driver and laser receiver. A lot of transmission lines would require a lot of laser drivers and laser receivers, as well as optical fibers. When the cost and the power consumption are increased, the product yield is also impacted significantly.
Optical signals can be used for an excellent transmission of high-speed signals, but for transmission of low-speed signals or when there is no signal input, the receiving end outputs noise, and an amplifier of a photo-electric chip can readily amplify the noise to an amplitude of a normal signal, which leads to errors.
Therefore, how to reduce transmission lines required by transmitting control signals of a plurality of multimedia interfaces, to transmit control signals in real time, and a high-speed transmission applicable for optical signals is a technical problem of the prior art in urgent need to be solved.